Early in the second act, Charlotte combines verbal irony with paradox as she ridicules Ephikhodof on her way off stage.
CHARLOTTE. That’s done. I’m off. [Slinging the rifle over her shoulder.] You’re a clever fellow, Ephikhódof, and very alarming. Women must fall madly in love with you. Brrr! [Going.]
Charlotte does not literally wish to compliment Ephikhodof, but instead uses verbal irony to insult him. Seemingly sick of listening to his music and reflections—or perhaps hurt that he isn't paying her any attention—she sarcastically calls him clever, alarming, and attractive. The final comment, that women must fall madly in love with him, seems aimed at taunting Ephikhodof for his unrequited love for Dunyasha, who literally stares at a mirror instead of noticing his advances.
Just before Charlotte delivers this line, Ephikhodof has taken a break from his guitar-playing to reveal that he always carries a revolver on him in case he decides to commit suicide. Charlotte's outburst can be interpreted in a number of ways, but it's possible that her disgust with Ephikhodof is a result of her hurt feelings.
The act opens with Charlotte delivering a monologue about her childhood and life while the other characters present on stage—Ephikhodof, Dunyasha, and Yasha—hardly seem to register that she's talking. Ephikhodof plays the guitar and sings some lines whose overall sentiment resembles Charlotte's thoughts, but he doesn't engage with her. Instead, the ensuing conversation between the characters revolves around the music and the experience of living abroad. Perhaps this is because they have heard it before; perhaps it's because they don't care about her. In either case, the play contains a great number of non-sequiturs, as Chekhov calls attention to the way in which people often neglect to listen to each other in conversations and instead prefer to talk about themselves. Charlotte seems bothered by the fact that Ephikhodof expresses emotions that run parallel to hers without responding to her.
Immediately after her ironic comments, Charlotte utters a paradox before exiting the stage.
These clever people are all so stupid; I have no one to talk to. I am always alone, always alone; I have no friends or relations, and who I am, or why I exist, is a mystery.
Like the verbal irony, the paradox is a criticism of the characters around her. By saying that the clever people are all stupid, she seems to be contradicting herself. However, her point is more that these people who are so convinced by their own cleverness are in fact stupid. This point adds meaning to her following lines. Although she isn't actually alone all the time, Charlotte's inability to take the characters around her seriously—and to feel like they're taking her seriously—makes her feel as though she's in constant isolation.